This invention relates to a system and process for separating contaminants from an effluent. More particularly, but not by way of limitation, this invention relates to a system and process for separating contaminants from a stream that is being produced from an oil and gas reservoir that has a pH of 7 or less.
In the oil and gas industry, operators will complete a well to a hydrocarbon bearing zone. An effluent will be produced from the well, with the effluent containing a mixture of hydrocarbons and water. At the surface, the effluent is separated into a hydrocarbon liquid phase, a hydrocarbon gas phase and a water phase as is well understood by those of ordinary skill in the art. The hydrocarbons are generally directed to processing facilities for sale and refinement. The produced water will be disposed by conventional methods. In offshore areas, this may entail releasing the water over board into the ocean. In other areas, the operator may choose to inject the produced water to a subterranean reservoir.
Many operators will attempt to increase the production of the well by performing acid stimulation to the reservoir. The acid stimulations require pumping large amounts of acid into the permeable formation, and thereafter, flowing the well in order to retrieve the spent acid as well as returning the well to normal production. The effluent being produced from the well will contain a mixture of at least the following components: a hydrocarbon liquid phase, a hydrocarbon gas phase, a spent acid compound, solids and water.
Due to the toxic nature of this type of effluent, the handling of the effluent is of concern to operators. Also, governmental regulations throughout the world have been promulgated that regulate the handling and disposal of these types of effluents. Also, if the effluent is recycled back into the production facilities, the effluent will cause equipment problems which can lead to equipment failures. The failure of equipment in these remote and offshore areas can cause significant problems to the safety and health of personnel and the environment as is well understood by those of ordinary skill in the art.
Prior art systems have been developed in order to segregate the various components constituting the effluent, and therefore, separate out the toxic, hazardous or otherwise unwanted components. These systems include, but not limited to: chemical treatments; separation in a gravity-type vessel; separation via a centrifuge separator; separation with filters. Each of these systems have some merit. However, the prior art systems fail for many reasons including limited success with proper separation, expense, amount of manpower required, further problems with contaminated treating fluids, disposal of treating media, lack of available injection wells, etc. This list is meant to be illustrative.
Therefore, there is a need for a system and process for treating oil and gas well fluids. There is also a need for a process whereby acid treatment flow back fluids can be handled. There is a need for an automated system of treating low pH effluents produced from oil and gas well bores whereby waste is minimized. There is a further need for a system that will treat production well fluids having a pH of 7 or less that will comply with government statutes and regulations. These and many other needs will be met by a reading of the following description.